As compared with an analog radio broadcasting, digital radio broadcasting has an advantage of providing various data services such as a text message, a slide show, traffic information, and a journal in addition to a high-quality stereo audio service.
Further, since the digital radio broadcasting can significantly reduce transmission power at the time of providing a service in the same range, several countries are preparing to convert the analog radio broadcasting into the digital radio broadcasting.
An orthogonal frequency division multiplexing (OFDM) based digital radio mondiale (DRM) plus system is a digital radio standard of Band I and II (47 to 174 MHz) and supports a data transfer rate of the maximum 185 kbps in a bandwidth of 100 kHz. Therefore, a lot of countries consider the DRM plus as the digital radio broadcasting which will replace the analog FM broadcasting.
However, in order to completely switch the analog broadcasting into the digital broadcasting (ASO: Analog Switch Off), listeners need some time to prepare for the switching, and as a result, broadcasting companies plan a hybrid broadcasting providing the analog FM broadcasting and the DRM plus broadcasting as shown in FIG. 1 in parallel.
In the hybrid broadcasting, a DRM plus broadcast receiver or an FM broadcast receiver needs to distinguish an analog FM signal and a DRM plus signal without prior information on a channel.
However, since a streaming based broadcasting system does not have a fixed training symbol like a packet based burst data transfer system, the streaming based broadcasting system detects a transmission signal using a Guard-Interval correlation. That is, the broadcasting system in the related art compares whether a guard-interval correlation calculation result of a received signal is larger than a predetermined threshold to detect a signal of which the guard-interval correlation calculation result is larger than the predetermined threshold.
However, when the DRM plus broadcast receiver detects the DRM plus signal through the guard-interval correlation under the circumstances that the DRM plus broadcast receiver cannot know which broadcasting signal is received, a signal detection probability is low and a probability of a false alarm is high as the signal is misrecognized.